THE PLACING OF SHADE TREES 
73 
(5) The Potted Type. —This is for streets where brick 
or stone paving monopolizes the space and makes natural 
tree growth and development impossible. It is extremely 
formal, and can be used for narrow streets lined with 
handsome buildings, or for a paved plaza or thoroughfare 
largely devoted to vehicular traffic, as in the case of the 
Park Avenue approach to the Grand Central Terminal in 
New York; sidewalks and street pavements cover all 
surface, leaving no place in which the usual street trees 
would have a chance to live. By planting small trees in 
tubs or boxes and placing these containers on the sidewalk 
or in the center of the driveway, these man-made obstacles 
may be overcome. They are similarly used in some of the 
streets of Paris, notably the Rue de Rivoli. The effect 
may be strikingly pleasing and highly desirable when 
ordinary tree planting is not possible, due to neglect to 
provide proper conditions in the original development, or 
to the necessity of meeting exceptional features in design. 
It is possible by this means to use different trees for 
succeeding seasons; but, on the other hand, much greater 
care is required to maintain them than to maintain trees 
planted in openings in the paving, and thus the expense 
is very greatly increased. 
(6) The Informal Type. —On country roads, especially 
in a rolling or a hilly country, or on secondary highways, the 
formality of trees in straight lines, at regular distances 
apart, and of uniform size and appearance is inappropriate, 
as well as being tiresome to those who may find it neces¬ 
sary to travel along such roads. In contrast to such 
arrangement, trees of many species may be scattered at 
irregular intervals along the roadside, but selected and 
arranged in such manner as to accentuate the natural 
beauties of the country through which the road passes. 
Such informal planting needs equally as much thought 
